Patent GB-190427844-A (GB)
Title: An Improved Method of Controlling Electric Lifts, Elevators, Conveyors, or any similar Contrivance having a Moving Car and Stations.
Inventor: JACOBY HENRY CHARLES EDWARD
Filed: 1904-12-20
Granted: 1905-12-07
Abstract: 27,844. Jacoby, H. C. E. Dec. 20. Stopping engines and trains.-Relates to means for controlling electric lifts, elevators, conveyers, and similar appliances having a moving car and stations, by the use of which the car is made to travel and stop automatically at selected points by the pressing of corresponding buttons of a series on the car or at any one of the various floors or stations. Figs. 1 and 2 show the invention applied to an electric lift with the cage a carrying a shaft d having a star-wheel f mounted thereon. Laterally-projecting rollers g between the teeth of the star-wheel engage the guide band normally prevent the star-wheel from rotating, but, when the teeth are engaged by the projections i on the guide, the rollers run in indentations j situated at each floor, and the star-wheel rotates. The shaft d is connected by a chain l to a shaft d<1> carrying as many cams n<1> ... n<5> as there are floors to the lift, these cams being fixed on the shaft in different angular positions and adapted to engage bars o<1> ... o<5>, integral with the magnet cores and polepieces p, by means of antifriction rollers q, thereby moving the magnet cores and the armatures s', s<5>, hinged or pivoted thereto, against the action of springs u, and causing projections y at the same time to engage rollers x on the armatures and force the contacts t' out of engagement with two adjacent contacts of the three shown at z, z<1>, z<11>. These contacts are connected to electromagnets used to reverse the motor-controlling switch. Pushbuttons 10 are provided on the cage to force the contacts into engagement when required. but the push buttons on the floors are utilized to energize electromagnets w, w<1> acting on the pivoted armatures s'. As soon as one of the armatures touches the contacts z, z<1>, z<11>, a circuit is completed through gate switches which is independent of the push-button circuit and retains the armature in position when the push-button is released. Fig. 4 shows the general arrangement of the lift with the cage a suspended by the rope 3 from the hoisting- drum 1, which is driven by the motor 2 controlled by the switch 5. The lower or holding magnets w have differential windings, the ratio of the number of turns in each windmg being different in the different magnets. The upper or attracting magnets are preferably wound so that the current can pass through either the whole or a portion of the winding. A resistance 11 is fixed on the third floor, preferably at the base of the push-button 8, and has its ends connected respectively to the two windings of the magnets w and also to one contact of the push-buttons 8 on the first and third floors. The push-buttons on the other floors have one contact connected to intermediate points of the resistance, and the arrangement is such that, when any button is pressed, the current divides and the two portions flow through different parts of the resistances 11 and then in opposite directions through the two windings of the holding- magnets w, and finally energize the attracting magnets w<1>. The holding-magnet corresponding to the floor on which the button was pressed is neutralized by the passage of the two currents, and the upper attracting-magnet forces the pivoted armature into engagement with two of the contacts z, z<1>, z<11>, thereby energizing one of the solenoids 6, 7 on the switch 5 and operating the motor. Gate switches 9 cut off the current to the motor when any of the gates are open. As the lift passes the various floors, the star-wheel mechanism is operated and pushes the corresponding armatures opposite to the contacts for actuating the cage in the opposite direction, and, when the selected floor is reached, the lever y, Fig. 2, engages the wheel x and breaks the circuit, thus stopping the lift. The holding-magnets w may be dispensed with, and separate wires with a common return employed for each push-button and attracting-magnet. An auxiliary resistance may be used in connection with the resistance 11. Resistance R, Fig. 4, is inserted as shown, or in the return wire, to shunt the button circuit across one of the magnets 6, 7, while the lift is working, and thus prevent interference after the lift has started. The star-wheel f may be attached directly, or geared in other suitable manner, to the shaft d, or a holding and attracting magnet with armature and contacts may be fixed on each floor, in which case a separate star-wheel on each magnet is operated by pegs on the cage.